How should I interpret ornery in this context?

Hi...I'm employed as a Spanish medical interpreter in a women's hospital here in Indianapolis. The reason I'm not asking this question in the medical forum is this is more of a general conversation type thing. Frequently, if the nurse is having trouble keeping a baby on the fetal heart monitor, or perhaps if the baby isn't head down and the doctor is having trouble turning him/her, the medical provider will say that the baby is being 'ornery'. (They're just using it in a friendly way.) When I look up ornery in the dictionary, I find irascible or intratable. I see that more as 'crotchety' or 'cantankerous'. What I'm trying to communicate is more like a stubbornness or being uncooperative. (Again, they're not trying to insult the family at all.) As a non-native speaker, I'm always at a loss as to how to say that. Any advice?